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Current terminology for zeroing in electrical installations vs grounding explained

pitertheb 49207 4
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Treść została przetłumaczona polish » english Zobacz oryginalną wersję tematu
  • #1 513618
    pitertheb
    Level 11  
    Hello again, my second question is about grounding and zeroing. I know that there is currently no such procedure as zeroing because it is called differently, so I would like to know what this procedure is now called and what it means (what it is), I would also like to ask you to explain what grounding is, what it consists of and what distinguishes it from once zeroing .
    Thank you very much for your answer.
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  • #2 513631
    Paweł.ko
    Electroacoustics specialist
    Earthing, as the name suggests, this earthing, i.e. a piece of metal, is buried in the ground (e.g. a backyard) and from this point a grounding wire (usually yellow-green) is pulled. It is (according to current electrical standards) the so-called protective zero. it has nothing to do with the working zero. The working zero is the neutral wire connected to the receiver. If there is no protective zero in the installation, i.e. grounding (such situations are often found in old buildings), it is permissible to zero, i.e. connect the protective pin with the working zero (in other words with we make a protective zero).
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  • #3 513633
    Nemo
    Level 31  
    Grounding is connecting, for example, the housing of the device to an earth electrode - a conductor buried in the ground, while zeroing is a connection to zero of the network. Both have advantages and disadvantages.
    Regards.
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  • #4 514401
    misiosoft
    Level 16  
    Hmm, it's a bit wrong.
    The performance is now called a TNS or TNC-S network connection, depending on whether a 2-wire or 3-wire network is used.
    The grounding is now called TT connection.
    In the TNS network system, all available conductive parts (i.e. the metal perimeter) are connected to the PE protective conductor, while in the TNC-S network to the PEN protective neutral conductor. In the TT network, all available parts are connected to the earth electrode. The short-circuit loop impedance in TN systems and the earthing resistance in the TT system should be selected so that the voltage is automatically disconnected (fuses tripped) in the event of a phase short-circuit with available conductive elements.

    And one more note, according to the new regulations, there is no such thing as a neutral conductor N, and it differs only in the name. The old electricians keep talking and they'll say 0.
  • #5 514492
    goscu
    Level 16  
    Okay, the Lord says Mr. Misio ... I can add that additional protection through the so-called zeroing (so say old electricians) in the TNC lattice; TNS or TNC-S (here we can also connect the N conductor with the housing, the PE conductor should be connected) is now called quick disconnection. The point is that in the event of a voltage breakdown, a current will flow into the housing that will cause the circuit's protection to work. The maximum times in which a quick disconnection is to occur for our network (230 V between the phase conductor and the earth) is 0.4 sec. under environmental conditions of the first 1 and 0.2 sec. in environmental conditions 2.
    These conditions depend on the ratio of the resistance of the human body to the earth. (in łazence it must be 0.2 sec).
    For this to happen, it is necessary to check the fault loop impedance and check the protection characteristics at what time the trip will occur (at the current resulting from the fault loop impedance).
    With the quick disconnect method, the housing of the device (e.g. washing machine) has a PEN conductor potential (so-called zero) for a given point in the network. You can check by putting an AC voltmeter between such a housing and, for example, a tap. Rather, the faucet has the potential of a zemi. it may be a few volts.
    Due to grounding, the housing has ground potential, but the resistance of such grounding must be appropriate, it depends on the network layout. (E.g. in the TT system, the shutdown time should be no longer than 5 seconds) ".
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